Chinese solar cell and panel manufacturer LONGi Solar announced a new bifacial module in May 2019 that uses larger solar cells than those it has traditionally made commercially available. The new Hi-MO4 module uses M6 (166-mm) wafers while LONGi’s older modules use M2 (156.75-mm) wafers.
Today the company announced it has received over 2 GW of orders for its Hi-MO4 module and will switch all its manufacturing lines to the larger wafer by next year.
“By end 2020, LONGi will upgrade its existing cell and module lines and transform them for production with 166-mm wafer,” said Wang Yingge, head of global marketing, LONGi Solar. “New lines, such as the 5-GW monocrystalline cell line in Yinchuan (China), will be designed for the 166-mm size from the start.”
A larger solar cell increases the area exposed to light, which can increase power and reduce cost. SunPower announced it was also increasing the size of its solar cells earlier this year to 160-mm (smaller than LONGi’s latest).
Differing wafer sizes will lead to a mismatch in processes and standards in the supply chain, said Li Zhenguo, president of LONGi Group. The company wants to get the rest of the industry on board with its larger cell size.
“If manufacturers cannot reach an agreement on a size standard, it will restrict the development of the whole industry,” Zhenguo said.
LONGi said that its existing crystal drawing and slicing equipment are easily adaptable to the larger wafer size, and the costs to update the equipment are lower and “easier to achieve.”
Professor Shen Wenzhong, director of the Solar Energy Research Institute of Shanghai Jiaotong University, said the larger wafer should increase LONGi’s annual capacity by 13%. Larger solar cells produce more power, and modules will be more powerful too. LONGi’s Hi-MO4 module is expected to reach 420 W. SunPower’s A-Series modules using its larger Maxeon cells have been rated at 400 W.